<!DOCTYPE html>
<html>
	<head>
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		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			new Promise((resolve, reject) => {
				setTimeout(() => {
					resolve('aaa')
				}, 1000)
			}).then(res => {
				console.log(res + '第一层的10行代码处理')
				return res + 1111
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				console.log(res + '第二层的10行代码处理')
				return res + 2222
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